Problem "OnPreDraw" 7.0.4

Hello everyone, happy new year!

My model was working fine and now suddenly when I run it suddenly it stops the animation and gives only error messages in the System Output. "exception: Exception caught in flexscript execution of VIEW:/active/MainPanel/BackPanel/SplitterXPane/SplitterYPane/TabPane/TabControl/Perspective>eventfunctions/OnPreDraw line 18 instruction 54. Discontinuing execution."
Then doesn't matter what I try to click or to close it, I see
"exception: size_t treewin__OnMouseMoveXX(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam, TreeWin * t, int mx, int my)
ex: t->mousemove(hWnd,mx,my);exception: treewin__OnMouseMove"

I have to force FlexSim to close through TaskManager. After restarting sometimes it works for a while and then suddenly it comes again, impossible to run for longer to gather statistics. Even saving as new model or copying tree into new model did not help to resolve the issue. I have Windows 7 professional and NVidia Quadro K2000M with FlexSim 7.0.4 64bit.

Any idea what is causing these errors and something I could do to fix it? Anyone had something similar? Thank you!

Do you have shaders turned on?

Originally Posted by Phil BoBo

Do you have shaders turned on?

No. And I tested now, if I let the simulation run without displaying the 3D model it runs for weeks. Only when displaying the 3D animation it is messed-up suddenly. I haven't done any changes (importing shapes etc.), just adjusting some task sequences and expanding the network (some new network nodes inside a container, could that cause trouble perhaps?). It was running smoothly in 7.0.4 before.

Something that might be model-specific would be exceptions in an object's draw code. That could be causing this type of error message and might happen at a certain point during the model run if the draw code logic is controlled by variables in the simulation.

You could send your model to Support to try to replicate the issue to determine whether it is model-specific or hardware/driver related.

If the model's draw code is fine, it might be related to the graphics driver for your graphics card. Line 18 of the Perspective's OnPreDraw is setting the shader program. If shaders are turned off, it is setting it to 0, which tells the card to not use shaders. I've seen some strange behavior with shaders on Quadros so this might be related.

okay, now when I activate shaders it works. As soon as I switch off it happens again. But its okay, model/project is almost finished, so I at least I got a quick fix I was hoping for

I started having same issues in other models as well while on other laptops my model ran without problems. So I decided to re-install FlexSim and now it works stable again :-)